Caoutchouc-cutting device



ons, 1929. iF. KEMPTER f l'1,730,821

- CAOUICHOUC CUTTING DEYMEE "Fi-19 'April 26. 1924 y i., i

Patented Oct. 8, 1929 UNITED STATES PATENT `OFFICE FRITZ KEMPTER, OFSTUTTGART, GERMANY CAO'UTCHOUC-CUTTING DEVICE Application led April 26,1924, Serial No 1u side faces of which the caoutchouc will adhere 'i fsothat the cutters "must overcome a com- "paratively great" resistance incutting and, when moving rapidly, will cause the caoutchoucto-be undulyheated. It has already i been proposed to force the block of rawcaoutchouc into a system of thin stationary cutters having. a lengthequalling t-he height of the block. However, cutters of this kind arerather fragile and are liable to be damaged by the foreign bodiespresent in the caoutchouc. Moreover, the slices of caoutchouc can beremoved from between the knives only with great difficulty.

The device according to the present invention comprises a wedge-shapedcutter arranged to be moved by means of a piston acted upon by asuitable pressure medium, this cutter being preferably short and adaptedto force the cut faces ofthe caoutchouc apart directly at the rear ofthe slit,thus preventing considerable frictional resistance fromarising. Any foreign bodies which may be present in the rawcaoutchouc-:can give Way without injuring the cutter'which, owing to itsparticular form, is far more resistive than an ordinary knife blade.

In the drawings affixed to this specification and forming part thereof adevice embodying my invention is illustrated'diagrammatically by way ofexample. In the drawings Fig. 1 is a front elevation and Fig. 2 a sideelevation of a hydraulic cutting device, while Figs. 3 and 4 are crosssections of different forms of a cutter:

The bed plate a carries two standards b serving as guides for a die scarrying the cut* ter which may consist of a wedge-shaped body e and aremovable cutting blade c fixed 709,317, and in Germany August 18, 1923.

to it by means of screws or the like and capable of being easilyreground.

The wedge-shaped carrier may have a symmetric cross section, as shown inFig. 3, or an asymmetric one (Fig. 4) In the latter case, oneof itsfaces (the one carrying the cutting blade c) extends in parallel to theplane of movement of the cutter, while the other face is disposed at anacute angle. The body portion e is removably attached to the piston of ahydraulic press, this piston being `arranged for reciprocation in thecylinder d.

In the operation of this device, the block of caoutchouc to be splitinto slices is sim ly placed on the bed plate underneath the we ge whichis now forced down upon it and, owing to its particular configuration,causes the single parts to be forced outwards.

The bed plate a may either carry a Wooden support which the blade caneasily enter into, or else a slot can be provided in the bed plate.

At some distance above the bed plate a there is arranged a frame Lcarrying rollers f resting on rails g. The caoutchouc block placed inthis frame is'fed forward with it after each stroke of the carrier andthe slices separated from the block rest on the frame h until the' blockis fully divided into slices, whereupon the frame is caused to move intoits end position shown in dotted lines on the left hand half of Fig. 2,where it projects beyond the edge of the bed plate, thereby allowing theslices of caoutchouc to drop into a portable container z'.

Preferably, this cutting device is operatively connected with ahydraulic accumulator of the kind generally used in rubber mills,` and,in that case, the control mechanism must be arranged for easy variationof stroke and for automatic return of the piston. However, thewedge-shaped carrier can as well v be moved by means of a lever or ascrew spindle and, instead of movin vertically, the device as a wholemight as we l be arranged in horizontal or inclined position.

With a cutter, such as shown in Fig. 4, in which the face extending inparallel to the plane of motion faces the piece of caoutchouc to besubdivided, this latter will not be forced 100 back by the wedge, butwill remain in place during` the cutting.

I Wish it to be understood that I do not desire to be limited to theexact details of construction shown and described, for obviousmodicatlons will occur to a person skilled in the art.

A caoutchouc cutting machine comprising a bed plate, a plunger adaptedto reciprocate vertically with respect to said bed plate, a spreadingWedge connected to said plunger the size of the base of said Wedge Whereit is connected With said plunger being larger than the diameter of saidplunger, and a cutter secured to s aid Wedge. I

In testimony whereof I affix my signature.

FRITZ KEMPTER.

